BS 592 : 1957 was made obsolete and superceded by BS 3100 : 1967. Grade B was replaced by designation A2.
Chemical composition is C 0.35; Si 0.60; Mn 1.0; P .06; S .06 (P and S tightened to .05 each in BS 3100 : 1991)
Mechanical Properties are 490 N/mm2 min Tensile; 260 N/mm2 min Yield; 18% min Elongation; 90 degree bend at 1.5t radius; 20J min Charpy V Notch Impact (noting that either bend or impact may be specified at customer's discretion)
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